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EccIntPointMult

Scalar multiplication of a point on an elliptic curve.

Syntax:

nP := EccIntPointMult(K,E,n,P);

finite field
  K  
list
  E  
integer
  n  
list
  P  
list
  nP  

See also:  EccPointsAdd, EccPointIsOnCurve, EccEncryptEccDecrypt, FF

Description:

Using the group law on an elliptic curve E over a finite field K a point P=[x,y] on E is multiplied by the scalar n. E is either given by a list of two or five elements of K or integers. If the equation of E is y^2=x^3+a_4 x+a_6 the curve is represented by [a_4,a_6], if the equation of E is y^2+a_1 xy+a_3y=x^3+a_2x^2+a_4 x+a_6 then the representation is [a_1,a_2,a_3,a_4,a_6]. Points on the curve are given by a pair of elements of K or integers; the point at infinity is represented by the empty list [\;].


Example:


kash> K := FF(11);
Finite field of size 11
kash> E := [0,0,0,1,6];
[ 0, 0, 0, 1, 6 ]
kash> EccIntPointMult(K,E,-1,[2,7]);
[ 2, 4 ]
kash> EccIntPointMult(K,E,5,[2,7]);
[ 3, 6 ]
kash> EccIntPointMult(K,E,12,[2,7]);
[ 2, 4 ]
kash> EccIntPointMult(K,E,13,[2,7]);
[  ]
kash> EccIntPointMult(K,E,14,[2,7]);
> [ 2, 7 ]


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